Running-board pump



D. G. EDWARDS. RUNNING BOARD PUMP.

APPLICATION FILED JAN-28,1920.

Patented Feb. 7, 1922'.

2 SHEETS-SHEET l- INVENTOR.

0. a. EDWA RDS. RUNNINGBOARD PUMP. APPLICATION F'ILED'JAN. 28, 1920.

1,405,908. Patented Feb. 7, 1922.

2 SHEETS-SHEET 2.

7 L z ngz mox. I

UNITED STATES PATENT OFFICE.

DANIEL. GORDQN EDWARDS, or HorxmsvrL E, KENTUCKY.

RUNNING-BOARD rumr.

Specification of Lettersjlatent.

Patented Feb. '7, 1922.

Application filed January 28, 1920. Serial No. 354,525.

Running-Board Pumps, of which the following 1s a specification.

The invention relates to reciprocating air pumps, and more particularly to pumpsespecially designed for the inflation of pneumatic tires, and adapted to be supported on the running board of an automobile.

The pump of the present invention is of a generally similar nature to that disclosed in and broadly claimed in my companion application Serial No. 352,297, filed January 19, 1920, in that it comprises means for positively expanding the piston during the working stroke, so as to prevent the escape of air past the same. therefore, the invention seeks toprovide an improved piston structure capable of being efi'ectively expanded, such structure being specifically different from that'of my said copending application. ,7

Another object of the present invention is to provide an improved lever mechanism for operating an expandingpiston ofithe-"ki-nd above referred'to when embodied in a pump of the running board type. I

With the above and'other; objects in view the invention consists in the construction and arrangement of parts hereinafter de scribed and claimed and illustrated in the accompanying drawings in which- Fig. 1 is a. plan View of my improved pump, with the operating handle removed. Fig. 2 is a side elevation thereof, the cylinder and part of the operating handle being shown in section, and

Figs. 3., 4: and 5- are fragmentary longi* tudinal sectional views on an enlarged scale, showing different constructions of piston which I may employ. I

Referring to the drawings in detail, 1 designates an elongated base or; frame; on which the pump is mounted, which base is adapted to be securedto the running board of an automobile by means of clamps 2;, one at each end of the base, and provided with set screws 3 or the like.

At one end of the base 1 is an up-standing bracket 4:, to which the cylinder head 5 is pivoted as at 6. The usual discharge nipple 8, containing a check valve, is carried have invented certain new and useful Improvements in In its broader aspects,

by the head 5 and adapted to be connected with a hose 9. The body orcylinder of the pump is indicated at 7, and preferably consists of a piece of brass tubing. It, is provided with the usual cap or cover 10, preferably having air holes 11, and through such cap freely passes a hollow piston rod 15. To the inner end of the piston rod is rigidl secured the piston, consisting, in the embodiment shown in Fig. 2, ofafelt washer 12, a flexible expansiblecup 14, and an interposed rigid plate or washer 13.

To the outer end of the hollow piston rod" 15 is secured a bracket 16, and this bracket is pivoted at 17*to a lever 18, intermediate its ends, one end of which lever is, itself, pivoted at 19to one of the clamps 2 carried by the base.

A pull rod. 20 extends through the hollow piston rod and is connected at the piston endto a valve and spreader, such as hereinafter described. The outer end of the ull rod 20 is provided with a collar 21 ant to this collar is pivoted, at 28, one end of an operating lever 22., ofiset as shown in Fig. 1 and fulcrumed intermediate its ends on a pivot pin 24 carried by the free end of the lever 18. A light helical spring 26 is preferably interposed between the bracket 16 and collar 21 and urges the pull rod 20' out wardly.

The upper end 25 of the lever 22 is shaped to fit in a socket 27 formed at the lower end of a detachable handle'28, as is common in this type of pump.

Referring now to Fig. 3, which illustrates one construction of piston, which I may employ, it will be seen that the end of the hollow piston rod 15 is screw threaded and car ries a lock nut 29, which secures the ele ments 12, 13 and 14 inposition. Inside of the expansible cup 14 which, in. this case, is preferably of flexible leather, is disposed a resilient cup shaped member 30, having a series of axially extending slots forming tongues between them. Fitting within the open end of this cup shaped member 30 is a spreader or expander consisting of a disc or block 34 preferably having air holes 35 formed therethrough. This disc orblock is carried on the screw threaded end-{20*- of; the pull rod 20 and is secured in position by means of lock nuts 36.

Secured to the extreme end of the hollow piston rod 15 is a valve seat consisting of a washer31 of leather, rubber or the like and adapted to co-operate with this valve seat is a valve 32 mounted on the threaded endof the rod 20, and adapted to be secured in adjusted position by means of a lock nut It will be noted that the spreader 34 is provided with tapering or sloping sides, which engage the free edges of the resilient cup 30 and it will be obvious that when a pull is exerted on the rod 20, the spreader will be forced into the cup, thereby extending the same,,so as to cause the'leather cup 13 to closel engage the cylinder walls. At the same time the valve 32 will be forced against its seat.

In Fig. 4 I have shown a modified construction in which a somewhat elongated leather cup 14 is employed and a correspondingly elongated cup shaped member 40 fits within the same and is provided, near its base, with an inclined portion 41. A rigid plate or washer 37 is preferably interposed between the cup 40 and the cup 14.

The spreader which I employ in this modification consists of a flat rigid disc 38 having air holes .39 and adapted to co-operate with the valve seat 31 to form a valve. It will be noted that as in Fig. 3, the edges of this spreader are sloping, as indicated at 42, and co-operate with the slanting portion 41 of the cup 40 to expand the same when a pull is exerted on the rod 20.

By using the expansion principle, as above described, it is possible to eliminate the leather cup entirely, and I have shown such an arrangement in Fig. 5. In this figure, I have illustrated an expander 34 similar to that shown in Fig. 3, but it is obvious that the form shown in. Fig. 4, in which the expander itself constitutes the valve, could equally well be employed. Referring again to Fig. 5, it will be. noted that in place of the leather cup 14 of Fig. 3, I have provided a thin expansible metal cup 43, which closely engages the cylinder walls. more or less resilient, being made, for example, of spring brass, and during the idle stroke of the piston it slides freely .in the cylinder. During the working stroke, however, a pull is exerted on the rod 20, as here inafter described and this forces the spreader 34 into the cup 43, thusv expanding the same into close contactwith the cylinder walls and making an air tight fit. With this construction, it is obvious that practical bdifliculties due to deterioration of leathe cups have been eliminated.

Referring again to Fig. 2, it will be seen that the parts are shown in the position which they occupy at the end of a. working stroke. In this position the spring 26 tends to hold the valve 32 seated and also urges the spreader into the cup to some extent. At

the beginning of the return or idle stroke,

however, the initial movement of the operat- This cup isv ing handle causes the lever 22 to turn slightly about its pivot 24, thus forcing the rod 20 inwardly against the tension of the spring 26, unseating the valve, and removingthe spreader from the cup. The expansible cup is, therefore, permitted to contact and can slide freely back through the cylinder, air meanwhile entering in front of the piston freely through the open valve 32.

At the beginning of the working stroke, the initial movement of the handle 28 causes the lever 22' to again swing slightly onits pivot 24, thus exerting a pull on rod 20 in the same directionas the spring 26 acts, such pull serving to seat the valve, and to freely press the spreader into the cup, thus expanding such cup. It will be noted that the greater the resistance encountered by the pis ten, the stronger the pull on the rod 20, and the greater the expanding action.

It will be seen that the elements 18, 22 and 28 form a compound lever, the parts of which are normally substantially in line, but

that at the beginning of the working stroke, the sections 22 and 28'are slightly displaced relative to the section 18, as shown in dot-ted lines in Fig. 2.

While I have shown my improved piston structure and lever mechanism as applied to a manually operated'pump of the running board type, it is apparent that the broad principles, involved may be equally well applied'to pumps of other types as for example pumps operated by engine power.

What I claim is r 1. In an air pump, the combination with a cylinder and piston, said piston c0mprising an expansible cup,'of'a spreader located within said cup, said spreader comprising a rigid non-yielding member, and means for positively forcing said spreader axially of the pump cylinder during the working stroke of the piston so as to expandsaid cup into close contact with the walls. of the cylinder, and for retracting said spreader durs ing the return stroke.

2. In anair pump,:the combination with a cylinder and piston, said piston comprising an expansible cup, of'a spreader located within said cup, said spreader comprisin a rigid, non-yielding member having slopln sides, and means for positively forcing sai spreader axially of the pump cylinder during the working stroke of the piston so as. to expand said cup intoclose contact with the walls of the cylinder, and for retracting said spreader during the return stroke.

3. In an air pump, the combination with a cylinder and piston, said'piston compris ing an expansible cup, of a valve seat carried by said piston, and a member within said expansible cup, adapted, when moved, to expand the same,'said member also co-operating with said valve seat. to form a valve.

4. In an air pump,-the combination with lOyO a cylinder and piston, said piston comprising a flexible cup, of a spreader located within said cup, and means for moving said spreader relative to the piston axially of the pump cylinder as the working stroke of the piston begins so as to cause it to expand said cup into close contact with the walls of the cy inder.

5. In an air pump, the combination with a cylinder and piston, said piston comprising an expansible cup, of a spreader in said cup, a base on which the pump cylinder is pivotally mounted, a lever pivoted to said base and mechanically connected with the piston, and a second lever, pivoted to the first, and mechanically connected with said spreader.

6. In an air pump, the combination with a cylinder and piston, saidpiston comprising an expansible cup, of a hollow piston rod on which said piston is mounted, a spreader in said cup, a pull rod secured to said spreader and extending through said hollow piston rod, a lever pivoted to said piston rod, and a second lever pivoted to thefirst and to said pull rod.

7 In an air pump, the combination with a cylinder and piston, said piston having a valve seat, of a valve adapted to co-operate with said seat, a base on which the pump cylinder is pivotally mounted, a lever pivoted to such base and mechanically con-' nected with the piston, and a second lever, pivot-ed to the first, and mechanically connected with said valve. 1

8. In an-air pump, the combination with a cylinder and piston, said piston having a valve seat, of a valveadapted to cooperate with said seat, a hollow piston rod on which said piston is mounted, a pull rod extendin through the piston rod and secured to said valve, a lever pivoted to said piston rod, and a second lever fulcrumed on the first, and connected with said pull rod.

9. In an air pump, the combination with a cylinder and piston, said piston having a valve seat, of a valve adapted to cooperate with said seat, a hollow piston rod on which said piston is mounted, a pull rod extendin through the piston rod and secured to sai valve, a spring interposed between said piston rod and pull rod and tending to seat the valve, and means for moving said pull rod relative to the piston rod to unseat said valve.

10. In an air pump, the combination of a base, a cylinder pivotally mounted thereon,

a piston in said cylinder havin a valve seat,

a valve co-operating with saic seat, a compound lever pivoted at one end to said base and operatively connected to said piston, and

means operated by the initial movement of said compound lever for actuating the valve before the piston begins to move.

11. In an air pump, the combination of a base, acylinder pivotally mounted thereon, a piston in said cylinder comprising an expansible cup, a compound lever pivoted at one end to said base and operatively connected with said piston, and means operated by the initial movement of said compound lever for expanding said cup into close contact with the cylinder walls before the piston begins its working stroke.

In testimony whereof I aflix my signature.

DANIEL GORDON EDWARDS. 

